Refers to the highest level of response a city's fire department may be placed on.

There are varying degrees of alertness that fire stations may be placed on:

¨ One Alarm Fire - typically sends out one unit to report on the status of an alarm. This is actually rare for most city fire departments, and involves small fires, or fires which have already been extinguished;

¨ Two Alarm - this is the standard response of one station to a fire;

¨ Three and Four Alarm - these involve increasing numbers of stations responding to the fire, working under the same jurisdiction or city; and

¨ Five Alarm fire - the fire is so large that outside help from other cities or municipalities is requested.